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[fixes #755] Correctly calculates mass override (particularly on stages)

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This commit is contained in:
Daniel_M_Williams 2020-09-02 22:33:39 -04:00
parent 5b94bedb5f
commit bd09354fd3
2 changed files with 81 additions and 34 deletions
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40
core/src/net/sf/openrocket/masscalc/MassCalculation.java
View File

@ -53,11 +53,9 @@ public class MassCalculation {
// =========== Instance Functions ========================
public void merge( final MassCalculation other ) {
if( MIN_MASS < other.getMass()) {
// Adjust Center-of-mass
this.addMass( other.getCM() );
this.bodies.addAll( other.bodies );
}
// Adjust Center-of-mass
this.addMass( other.getCM() );
this.bodies.addAll( other.bodies );
}
public void addInertia( final RigidBody data ) {
@ -320,25 +318,11 @@ public class MassCalculation {
}
}
if( MIN_MASS < children.getMass() ) {
this.merge( children );
// // vvv DEBUG
// System.err.println(String.format( "%s....assembly mass (incl/children): %s", prefix, this.toCMDebug()));
}
this.merge( children );
if (this.config.isComponentActive(component) ){
Coordinate compCM = component.getComponentCG();
if (!component.getOverrideSubcomponents()) {
if (component.isMassOverridden()) {
compCM = compCM.setWeight(MathUtil.max(component.getOverrideMass(), MIN_MASS));
// // vvv DEBUG
// System.err.println(String.format( "%s....mass overridden to: %s", prefix, compCM.toPreciseString()));
}
if (component.isCGOverridden())
compCM = compCM.setXYZ(component.getOverrideCG());
}
// mass data for *this component only* in the rocket-frame
compCM = parentTransform.transform( compCM.add(component.getPosition()) );
if (component.getOverrideSubcomponents()) {
@ -351,18 +335,24 @@ public class MassCalculation {
if (component.isCGOverridden()) {
this.setCM( this.getCM().setX( compCM.x + component.getOverrideCGX()));
}
}else {
if (component.isMassOverridden()) {
compCM = compCM.setWeight(MathUtil.max(component.getOverrideMass(), MIN_MASS));
}
if (component.isCGOverridden()) {
compCM = compCM.setXYZ(component.getOverrideCG());
}
this.addMass( compCM );
}
this.addMass( compCM );
if(null != analysisMap){
final CMAnalysisEntry entry = analysisMap.get(component.hashCode());
if( component instanceof ComponentAssembly) {
// For ComponentAssemblies, record the _assembly_ information
CMAnalysisEntry entry = analysisMap.get(component.hashCode());
entry.updateEachMass(children.getMass() / component.getInstanceCount());
entry.updateAverageCM(this.centerOfMass);
}else{
// For actual components, record the mass of the component, and disregard children
CMAnalysisEntry entry = analysisMap.get(component.hashCode());
entry.updateEachMass(compCM.weight);
entry.updateAverageCM(compCM);
}

75
core/test/net/sf/openrocket/masscalc/MassCalculatorTest.java
View File

@ -160,7 +160,7 @@ public class MassCalculatorTest extends BaseTestCase {
}
@Test
public void testStageOverride() {
public void testStageCMxOverride() {
final Rocket rocket = TestRockets.makeSimple2Stage();
final AxialStage sustainerStage = (AxialStage) rocket.getChild(0);
final AxialStage boosterStage = (AxialStage) rocket.getChild(1);
@ -181,28 +181,85 @@ public class MassCalculatorTest extends BaseTestCase {
final double actualRocketDryMass = actualStructure.cm.weight;
final double expRocketDryMass = 0.0081178754;
assertEquals(" Alpha III Empty Mass is incorrect: ", expRocketDryMass, actualRocketDryMass, EPSILON);
assertEquals(expRocketDryMass, actualRocketDryMass, EPSILON);
final Coordinate actualRocketDryCM = actualStructure.cm;
final double expCMx = 0.10;
assertEquals("Simple Rocket CM.x is incorrect: ", expCMx, actualRocketDryCM.x, EPSILON);
assertEquals(expCMx, actualRocketDryCM.x, EPSILON);
}
boosterStage.setOverrideSubcomponents(true);
boosterStage.setCGOverridden(true);
boosterStage.setOverrideCGX(0.0);
{ // [1] test Rocket CM, before:
final RigidBody actualStructure = MassCalculator.calculateStructure(config);
final double actualRocketDryMass = actualStructure.cm.weight;
final double expRocketDryMass = 0.0081178754;
assertEquals(expRocketDryMass, actualRocketDryMass, EPSILON);
final Coordinate actualRocketDryCM = actualStructure.cm;
final double expCMx = 0.075;
assertEquals(expCMx, actualRocketDryCM.x, EPSILON);
}
}
@Test
public void testStageMassOverride() {
final Rocket rocket = TestRockets.makeSimple2Stage();
final AxialStage sustainerStage = (AxialStage) rocket.getChild(0);
final AxialStage boosterStage = (AxialStage) rocket.getChild(1);
final FlightConfiguration config = rocket.getSelectedConfiguration();
{ // [0] verify / document structure
final double expMass = 0.0040589377;
final BodyTube sustainerBody = (BodyTube) sustainerStage.getChild(0);
assertEquals(0.0, sustainerBody.getPosition().x, EPSILON);
assertEquals(0.1, sustainerBody.getLength(), EPSILON);
assertEquals(expMass, sustainerBody.getMass(), EPSILON);
final BodyTube boosterBody = (BodyTube) boosterStage.getChild(0);
assertEquals(0.10, boosterBody.getComponentLocations()[0].x, EPSILON);
assertEquals(0.10, boosterBody.getLength(), EPSILON);
assertEquals(expMass, sustainerBody.getMass(), EPSILON);
}
{ // [1] test Rocket CM, before:
final RigidBody actualStructure = MassCalculator.calculateStructure(config);
final double actualRocketDryMass = actualStructure.cm.weight;
final double expRocketDryMass = 0.0081178754;
assertEquals(" Alpha III Empty Mass is incorrect: ", expRocketDryMass, actualRocketDryMass, EPSILON);
assertEquals(expRocketDryMass, actualRocketDryMass, EPSILON);
final Coordinate actualRocketDryCM = actualStructure.cm;
final double expCMx = 0.075;
assertEquals("Simple Rocket CM.x is incorrect: ", expCMx, actualRocketDryCM.x, EPSILON);
final double expCMx = 0.10;
assertEquals(expCMx, actualRocketDryCM.x, EPSILON);
}
final BodyTube boosterBody = (BodyTube) boosterStage.getChild(0);
final double bodyMass = boosterBody.getMass();
assertEquals(0.0040589377, bodyMass, EPSILON);
boosterStage.setOverrideSubcomponents(true);
boosterStage.setMassOverridden(true);
boosterStage.setOverrideMass(bodyMass);
boosterBody.setOverrideSubcomponents(false);
boosterBody.setMassOverridden(true);
boosterBody.setOverrideMass(0.0);
{ // [1] test Rocket CM, before:
final RigidBody actualStructure = MassCalculator.calculateStructure(config);
final double actualRocketDryMass = actualStructure.cm.weight;
final double expRocketDryMass = 0.0081178754;
assertEquals(expRocketDryMass, actualRocketDryMass, EPSILON);
final Coordinate actualRocketDryCM = actualStructure.cm;
final double expCMx = 0.10;
assertEquals(expCMx, actualRocketDryCM.x, EPSILON);
}
}
@ -869,7 +926,7 @@ public class MassCalculatorTest extends BaseTestCase {
double calcTotalMass = structure.getMass();
assertEquals(" Booster Launch Mass is incorrect: ", expMass, calcTotalMass, EPSILON);
final double expCMx = 1.1191303646;
final double expCMx = 0.76762318688;
Coordinate expCM = new Coordinate(expCMx, 0, 0, expMass);
assertEquals(" Booster Launch CM.x is incorrect: ", expCM.x, structure.getCM().x, EPSILON);
assertEquals(" Booster Launch CM.y is incorrect: ", expCM.y, structure.getCM().y, EPSILON);
@ -877,11 +934,11 @@ public class MassCalculatorTest extends BaseTestCase {
assertEquals(" Booster Launch CM is incorrect: ", expCM, structure.getCM());
// Validate MOI
final double expMOI_axial = 0.005885793421431532;
final double expMOI_axial = 0.0038576236;
double boosterMOI_xx = structure.getRotationalInertia();
assertEquals(" Booster x-axis MOI is incorrect: ", expMOI_axial, boosterMOI_xx, EPSILON);
final double expMOI_tr = 0.04098909591063;
final double expMOI_tr = 0.123258667252;
double boosterMOI_tr = structure.getLongitudinalInertia();
assertEquals(" Booster transverse MOI is incorrect: ", expMOI_tr, boosterMOI_tr, EPSILON);
}